Zucchini-Tomato-Onion Gratin

The farm stands here in Prince Edward County are brimming with so much beautiful produce right now. I picked up a huge Zucchini the other day for .75 cents! This weeks recipe is a delicious way to serve up those gorgeous tomatoes, zucchini and onions that are available at all the local farms. I have been making this dish for many years, and it is something my mother made often when I was growing up. It is easy to make, can be prepared well in advance and the serving size can be adjusted to suit your needs. I make mine in the 8″ round casserole dish pictured above, which is about 5″ deep. It holds about 3 layers of each vegetable, depending on how thick you slice them. I like to keep all the slices about 1/4″ thick. Any thinner, they tend to just turn to mush after cooking. Any thicker just seems a bit much! Normally, I use Parmesan cheese and fresh basil in mine, but you could easily substitute another cheese and dried basil. You may also use extra Parmesan on the top layer if you prefer things extra cheesy. I hope you enjoy this family favourite summertime casserole!


1 large zucchini (or 2 medium), sliced into 1/2″ slices

2 large tomatoes, sliced into 1/2″ slices

1 large white onion, sliced

approx. 12 fresh basil leaves, cut into thin strips

3/4 cup grated Parmesan

salt and pepper to taste

Approx. 3 Tbsp Olive oil or oil of choice

1 tsp. butter



Grease the casserole dish with butter. Start with a layer of zucchini, then a layer of onion and then tomatoes. Drizzle 1 Tbsp of olive oil over tomatoes, then sprinkle with a couple tablespoons of Parmesan cheese and some of the basil strips. Season to taste with salt and pepper. Repeat the layers, drizzling oil & sprinkling Parmesan, basil, salt & pepper on each tomato layer. Make the tomatoes your final layer and top with remaining oil, basil, cheese, salt and pepper. Bake in a 350 degree oven for approximately 35-40 minutes, or until a knife can be inserted with no resistance.



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